1. Sugar: Sugar weakens the immune system drastically. One study looked at the response of neutraphils (a type of white blood cell) and their ability to engulf and destroy bacteria. It showed that only 3.5 oz of sugar reduced neutraphil function by 50% in just 30 minutes after ingestion (2).
2. Sleep deprivation: Chronic sleep deprivation decreases spleen weight and lymphocyte count (another type of white blood cell). The spleen is an important organ involved in the immune system acting as a filter for blood, a recycle site for red blood cells, and a storage compartment for platelets and white blood cells. The spleen also helps fight bacterial strains that cause pneumonia and meningitis. (1)
3. Chronic stress: The connection between chronic stress and the immune system has been known since the time ancient Greece. Today, there are many studies linking all types of stressors (emotional, physical, traumatic, environmental…) to reduced immunity. Stress increases the hormones epinephrine, norepinephrine, and cortisol, which in addition to weakening the immune system cause an inflammatory response, and weaken beneficial gut bacterial, stomach acid (HCl), and segratory IgA, all of which defend against unwanted microbes. Stress also increases the risk of sleep deprivation, cravings for junk food, and drug and alcohol abuse.
4. Sedentary lifestyle: Without exercise, we deprive the body of oxygen. Exercise oxygenates the body which supports energy production and the function of some beneficial bacteria in our digestive system, where over 70% of our immune system resides. Exercise is also essential for proper function of the lymph nodes. These tiny powerhouses defend the body against disease by producing and storing white blood cells, among other immune-supporting functions. Read more at Livestrong.com.
5. Processed diet: the Standard American diet (SAD) is high in processed food and low in essential nutrients that support the immune system, including zinc, magnesium, B-vitamins, vitamin D, and vitamin C.
Ok, so in addition to eating a low-sugar whole-food diet, getting adequate sleep each night, reducing stress, and moving the body, here are some strategies for boosting the immune system…
1. Increase Vitamin D: We usually reach for the C when we start to feel sick; and yes, vitamin C is important, but don’t forget about D. It plays an enormous role in immunity! A low vitamin D level is directly related to increased susceptibility to infection. Scary but true, researchers estimate that over 50 percent of the general public is deficient(3)! Increase vitamin D with foods including wild salmon, sardines, organic whole milk and pasture-raised eggs. Supplement with vitamin D3 and get your levels tested! Optimal blood levels are 50-70 ng/ml (3). For comparison, the last I checked, mine was 27ng/ml! You may be surprised that even in Colorado, with 300+ days of sunshine, we still need to supplement. Vitamin D deficiency puts you at greater risk for osteoporosis, cancer, and auto-immune conditions… Nothing to mess around with. See Dr. Mercola’s article for more information.
2. Take a probiotic: Beneficial gut bacterial plays many roles in our body; immunity is just one of them. All will agree with Ann Louise Gittleman, one of my biggest inspirations, when she said, “Good health is paved with good intestines.” Good bacteria keep pathogens from colonizing and proliferating. Take a high potency probiotic (15-25 billion strands per capsule) through the cold and flu season.
3. Increase zinc, vitamin C, and magnesium: A daily supplement of these nutrients, or better yet, a high quality multi-vitamin, will offer support. Taking a multi-vitamin assures these nutrients, particularly zinc and magnesium, are in balance with their cohorts. Be careful taking zinc in isolation; excess can cause imbalances in other nutrients and can be toxic. You may want to consult a pro. I recommend multi-vitamins from Designs for Health and Thorne.
4. Keep fingers clean and out of your nose, eyes, and mouth! Germs enter the body through orifices; so if you’re going to rub your eyes or pick your nose, be sure to scrub those hands with soap and hot water (especially under finger nails) before doing so.
5. Add immune-enhancing foods to your diet
- Garlic is a potent anti-microbial, anti-viral super food! It also stimulates the proliferation of many immune and detoxification components. Add raw garlic to pesto (see recipe below), salad dressing, tomato sauce, or chicken broth.
- Whey (if you can tolerate dairy) contains several immune-enhancing compounds, glutamine- a key nutrient for intestinal health- and antioxidants. I recommend organic kefir or yogurt. My favorite brands of yogurt are Nancy’s, Wallaby, and White Mountain Foods. These companies don’t use genetically modified feed, hormones, or thickening agents (4). If you use whey protein powder, be sure to use an undenatured variety; they contain higher amounts of immune-boosting goodness.
- Fermented foods like yogurt, kimchi, and sauerkraut are packed full of probiotics that support the GI tract and therefore enhance immune function. It’s easy (and cheap!) to make your own sauerkraut. Check out this recipe.
As the weather gets colder, I also recommend eating warming foods to nourish the soul and help the body accumulate to the changing season. Choose soups, stews, and curry over salad, a larger serving of cooked vegetables over raw ones, and warming spices including cayenne, cinnamon, ginger, cardamom, pepper, and horseradish.
(1) WebMD (2014). Digestive Disorders Health Center. Available at http://www.webmd.com/digestive-disorders/picture-of-the-spleen
(2) Bauman, E (2015). The Immune System, Therapeutic Nutrition Textbook, Part 2. Penngrove CA.
(3) Mercola (2012). Why Vitamin D is Better than Any Vaccine and Improves Your Immune System by 3-5 Times. Available at http://articles.mercola.com/sites/articles/archive/2012/01/04/why-this-vitamin-is-better-than-any-vaccine-and-improves-your-immune-system-by-35-times.aspx
(4) O’Connell, E. (2013). GMO Yogurt: How does your favorite brand stack up? Available at http://gmoinside.org/gmo-yogurt-how-does-your-favorite-brand-stack-up-2/